From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Accelerometer and stopwatch tests for tractive resistance and acceleration.
| Identifier | ExFiles\Box 113\2\ scan0011 | |
| Date | 18th December 1922 | |
| Y1725 18.12.22. ACTUAL READINGS - ACCELEROMETER TESTS CHECKED BY STOP WATCH. Tractive resistance tests. Top gear 20/10 m.p.h. Ashbourne Rd. Very slight gradient. Down Up Mean Down Up Mean Time - 45 2/5 18 1/5 31.1 50 1/5 18 2/5 34.5 Accelerometer. lbs per ton 38 10 24 35 14 24½ Formula used - N/t X 103 = Tract: resist: in lbs. per ton. t = Time in secs., N = drop in m.p.h. Almost level stretch between Ashbourne and Mayfield. Tract resistance. Time. 11 4/5 23 17 4/5 Accelerometer, lbs per ton 75 45 100 40/30 m.p.h. 30/20 m.p.h. top gear engine breaking 30/20 mph. Acceleration Tests - top gear. fairly level piece of road. 20/30 m.p.h. 10/20 m.p.h. Time 1.5 1.8 Accelerometer. f.p.s.² 8 4/5 8 Formula used - N/t x 1.47 = acceler: f.p.s/p.s. ( N & T have values as above) 2nd. gear. Fairly level piece of road. 10 - 20 m.p.h. Time 4 4/5 5 secs. Accelerometer. 2.7 2.85 LAR | ||